nitg: Extract exec_and_check from Android

[nit.git] / src / toolcontext.nit

diff --git a/src/toolcontext.nit b/src/toolcontext.nit
index 85d7cd6..f313063 100644 (file)
--- a/src/toolcontext.nit
+++ b/src/toolcontext.nit
@@ -133,6 +133,30 @@ class ToolContext
                        print "{s}"
                end
        end
+       
+       fun exec_and_check(args: Array[String], error: String)
+        do
+                var prog = args.first
+                args.remove_at 0
+
+                # Is the wanted program available?
+                var proc_which = new IProcess.from_a("which", [prog])
+                proc_which.wait
+                var res = proc_which.status
+                if res != 0 then
+                        print "{error}: executable \"{prog}\" not found"
+                        exit 1
+                end
+
+                # Execute the wanted program
+                var proc = new Process.from_a(prog, args)
+                proc.wait
+                res = proc.status
+                if res != 0 then
+                        print "{error}: execution of \"{prog} {args.join(" ")}\" failed"
+                        exit 1
+                end
+        end
 
        # Global OptionContext
        var option_context: OptionContext = new OptionContext
@@ -238,5 +262,31 @@ class ToolContext
                        # Make sure the output directory exists
                        log_directory.mkdir
                end
+
+               nit_dir = compute_nit_dir
+       end
+
+       # The identified root directory of the Nit project
+       var nit_dir: nullable String
+
+       private fun compute_nit_dir: nullable String
+       do
+               # a environ variable has precedence
+               var res = "NIT_DIR".environ
+               if not res.is_empty then return res
+
+               # find the runpath of the program from argv[0]
+               res = "{sys.program_name.dirname}/.."
+               if res.file_exists and "{res}/src/nit.nit".file_exists then return res.simplify_path
+
+               # find the runpath of the process from /proc
+               var exe = "/proc/self/exe"
+               if exe.file_exists then
+                       res = exe.realpath
+                       res = res.dirname.join_path("..")
+                       if res.file_exists and "{res}/src/nit.nit".file_exists then return res.simplify_path
+               end
+
+               return null
        end
 end